1. Field of the Invention
The present invention relates to a process for producing a compound exhibiting radical reaction activity, and in particular, a polymer compound exhibiting radical reaction activity. More specifically, the invention relates to a process for producing a polymer compound that has an unsaturated double bond in a side chain and is useful, for example, as an image forming material in view of productivity, sensitivity and strength.
2. Description of the Related Art
Compounds having a (meth)acryloyl group or a (meth)acrylamide group, which contain an α,β-unsaturated carbonyl group exhibiting high reactivity, in a side chain are widely utilized as polymerizable materials for image forming (e.g., in three-dimensional optical modeling and holography, and as planographic printing plate materials, color proofs, photoresists, and color filter) and as photo-curable resin materials (e.g., an ink, a paint and an adhesives). (As used herein, the term “(meth)acryl” refers to either one or both of “acryl” and “methacryl”.)
As a process for synthesizing a compound having a (meth)acryl group or a (meth)acrylamide group exhibiting high radical reaction activity, for example, a method for preparing the compound by causing a reaction between (meth)acrylic halide or (meth)acrylic anhydride and a compound having a functional group including an active hydrogen such as a hydroxyl group or an amino group is generally known. However, when a compound having a plurality of the above groups in one molecule is synthesized by the method, the reaction may occasionally be uncompleted or side reactions may occur to generate a contaminated crude product. Therefore, it is difficult to produce a desired compound having a double bond at high purity using this method.
As processes for introducing a (meth)acryl group or a (meth)acrylamide group exhibiting high radical reaction activity into a side chain of a polymer compound, a method utilizing a reaction between a polymer compound having a carboxylic acid in a side chain and an epoxy compound containing a (meth)acryl group or a compound containing a (meth)acryl group and a hydroxyl group, a method utilizing a reaction between a polymer compound having an epoxy group in a side chain and a carboxylic acid compound containing a (meth)acryl group, and a method utilizing a reaction between a polymer compound having an acid anhydride and a compound containing a (meth)acryl group and a hydroxyl group, which are described in Japanese Patent Application Publication (JP-B) No. 51-37316, are known. These reactions require a relatively high reaction temperature and involve disadvantages of easily inducing a polymer crosslinking reaction and gelation. Japanese Patent Application Laid-Open (JP-A) No. 2000-248024 discloses a method of introducing a (meth)acryl group into a side chain by effecting a reaction between a polymer compound having a carboxylic acid or a hydroxyl group and a (meth)acryl compound having an isocyanate group. These reactions also require a relatively high reaction temperature, and are associated with disadvantages in that a polymer crosslinking reaction may occur and gelation may often take place. Therefore, when a polymer compound obtained by these methods and containing an unsaturated group in a side chain is used in an image forming material, there arises a problem of poor removability at non-image areas. Furthermore, these methods are not preferred because the functional groups in the polymer side chains may react with each other, for example, through a reaction with an amide group in a side chain, to thus generate undesired products in view of purity.